Process of producing a soy product having improved sorption

ABSTRACT

The process of preparing a bland, free-flowing, non-hydroscopic soy product with improved liquid sorption and fat binding properties is disclosed; the process involving treatment of substantially dehulled, defatted and desolventized soy meal or flakes with an aqueous-alkaline solution, such as an aqueous calcium hydroxide solution, to solubilize and remove at least about 60% of the aqueous-alkaline soluble substances such as protein and carbohydrate materials from the flakes, separating the extracted soy meal product from the extract and thereafter drying the extracted product under controlled conditions. The resulting soy product is lighter in color, bland in taste and displays significantly improved liquid sorption and emulsifying properties which render it useful as a thickening agent, emulsifying agent, carrier, humectant, bulking agent, or sorbent in industrial or edible applications. The product is particularly useful as an emulsifying agent for a wide variety of food uses and has been found to produce food products having improved emulsion properties when used at the proper levels. An improved food product containing the soy product is also disclosed.

United States Patent [191 Starr [4 1 May 20, 1975 [75] Inventor: RobertP. Starr, Spanish Lake, Mo.

[73] Assignee: Ralston Purina Company, St. Louis,

[22] Filed: Nov. 9, 1973 [21] Appl. No.: 414,553

Related US. Application Data [63] Continuation of Ser. No. 144,324, May17, 1970, abandoned, which is a continuation-in-part of Ser. No.643,342, June 5, 1967, abandoned.

[52] US. Cl. 426/250; 426/148; 426/177; 426/212; 426/224; 426/364;426/371; 426/382; 426/471 OTHER PUBLICATIONS Ziemba, J. V., Let SoyProteins Work Wonders for You, Food Engineering, May 1966, pp. 82-91.

Primary Examiner-Raymond N. Jones Assistant Examiner-R. A. YoncoskieAttorney, Agent, or FirmVirgil B. Hill [5 7] ABSTRACT The process ofpreparing a bland, free-flowing, nonhydroscopic soy product withimproved liquid sorption and fat binding properties is disclosed; theprocess involving treatment of substantially dehulled, defatted anddesolventized soy meal or flakes with an aqueous-alkaline solution, suchas an aqueous calcium hydroxide solution, to solubilize and remove atleast about 60% of the aqueous-alkaline soluble substances such asprotein and carbohydrate materials from the flakes, separating theextracted soy meal product from the extract and thereafter drying theextracted prodnot under controlled conditions. The resulting soy productis lighter in color, bland in taste and displays significantly improvedliquid sorption and emulsifying properties which render it useful as athickening agent, emulsifying agent, carrier, humectant, bulking agent,or sorbent in industrial or edible applications. The product isparticularly useful as an emulsifying agent for a wide variety of fooduses and has been found to produce food products having improvedemulsion properties when used at the proper levels. An improved foodproduct containing the soy product is also disclosed.

9 Claims, N0 Drawings 1 PROCESS OF PRODUCING A SOY PRODUCT HAVINGIMPROVED SORPTION BACKGROUND OF THE INVENTION This application is acontinuation of application Ser. No. 144,324 entitled SOY PRODUCT HAVINGIM- PROVED SORPTION PROPERTIES AND PROCESS filed on May 17, 1970, whichapplication is 'a continuation-impart of US. application Ser. No.643,342 filed June 5, 1967, and are now abandoned.

The present invention is in the field of processes or methods forpreparing soy products and more particularly in the field of processesfor preparing soy products having liquid sorption and fat binding oremulsifying properties and to improved food products incorporating saidsoy products.

Heretofore, there have been available various soy materials which havebeen marketed for industrial and edible purposes and which exhibit wateror fat binding properties to some extent. Three such products are thoseknown to the art as soy flour or grits, Soy Protein Concentrate andIsolated Soy Protein. Soy flour represents the entire soy flake withonly the oil having been removed from the bean. While this product hasproven nutritive properties and has shown some merit for its functionalproperties as an additive, such as for purposes of moisture retention,for example, it has been subject to definite limitations in its use informulations due to flavor and other undesirable characteristics. SoyProtein Concentrate represents mainly the fibrous and protein fractionsof the soy flakes or meal, the bulk of the water-soluble carbohydratefraction having been removed. Isolated Soy Protein represents mainly theprotein fraction of soy flakes or meal, both the water-solublecarbohydrate and fibrous fractions having been removed. These refinedsoy products have been offered to the trade for their improvednutritive, flavor and absorptive characteristics. However, there hasremained an unfulfilled need for a soy product having equal or superiorflavor and nutritive properties as compared with soy products nowcommercially available, having significantly improved liquid sorptionand emulsifying or fat binding characteristics and which can be producedcommercially on an economical and competitive basis. It is also known toemploy emusifying agents in foods to bind fat and water. However, I havediscovered that food emulsion products containing my new soy materialhave greatly improved properties compared to products heretofore known.

SUMMARY OF THE INVENTION Therefore, among the several objects of theinvention may be noted the provision of a process of preparing a soyproduct which exhibits significantly improved liquid sorption andemulsifying characteristics rendering the product commercially usefulfor various edible and non-edible applications; the provision of such aprocess which produces a soy product of acceptable flavor and nutritiveproperties for use in various edible formulations; the provision of aprocess of the type indicated which employs, as the starting material,defatted and dehulled soy meal or flakes and results in the modificationof an extracted soy product; the provision of such a process which iseconomical and reliable to practice on a commercial scale; and theprovision of an improved soy product produced by the process. It is alsoan object of this invention to produce an improved food product havingimproved emulsion properties and a process for producing the improvedfood product. Other objects and features will be in part apparent and inpart pointed out hereinafter.

The present invention is thus directed to the method of producing asubstantially bland, free-flowing nonhydroscopic soy product havingimproved liquid sorption and emulsifying properties comprising the stepsof treating substantially dehulled, defatted and desolventized soy mealwith an aqueous alkaline material to solubilize and extract therefrom atleast approximately 60% of the aqueous-alkaline soluble substances,separating the resulting extracted soy meal product from the extract anddrying the extracted soy meal product under controlled drying conditionsto substantially avoid deleterious modification of the cellularstructure of said product. .The invention is also directed to the novelsoy product produced by the process of the invention which ischaracterized by novel properties and to improved food productsincorporating the novel soy product.

DESCRIPTION OF THE PREFERRED EMBODIMENTS As the starting material in mynovel process, I employ substantially dehulled, defatted anddesolventized soy meal or spent flakes prepared from sound, cleansoybeans. For best results, the meal or flakes should be as free ofhulls, weed seeds and trash as is practicable, although it will beunderstood that useful products may also be prepared in accordance withthe invention by employing spent flakes in the form generally availablein the trade. Defatting or removal of the oil fraction from the soybeansis carried out by conventional methods through the use of hexane orother similar hydrocarbon solvents, and the solvent extracted product isthen desoluentized in the conventional manner known to the art. Theresulting dehulled, defatted and desolventized soy meal or flakespreferably have a high dispersible protein content for use in theprocess of the present invention.

In carrying out the process of the invention, the soy meal or flakes arefirst treated with an aqueous alkaline agent in order to effectsolubilization and removal of the bulk of protein, carbohydrate and anyother aqueous-alkaline soluble substances from the defatted flakes. Forthis purpose, any suitable aqueous-alkaline solvent may be employed.Illustrative alkaline or basic materials which may be utilized includealkali metal hydroxides, such as sodium and potassium hydroxide,alkaline earth hydroxides, such as calcium hydroxide, alkali metalcarbonates, such as sodium carbonate, ammonium hydroxide and lime. Theextraction treatment may be carried out in one step, or if desired, mayinvolve two or more steps in one of which an aqueous medium containingno alkaline material is utilized as the extracting medium. Typically,the aqueous-alkaline agent employed for extracting the aqueous-alkalinesoluble substances may contain approximately 1-2 percent by weight ofthe alkaline material based upon the weight of the defatted soy flakes.However, it will be understood that the amount of alkaline material inthe aqueous-alkaline extracting agent may be varied widely to give thedesired removal of the aqueous-alkaline soluble substances as discussedhereinafter. Also, the extraction time may be varied to obtain thedesired degree of removal of aqueous-alkaline soluble substances fromthe starting material. Typically, the extraction time may be 30-60minutes. Further, heat of up to 180 F. may be applied during theextraction step to expe dite extraction of the soluble carbohydrate andproteinaceous materials. It is also preferred to employ known mechanicalmethods, such as stirring or agitating of the soy meal aqueous-alkalineslurry, during extraction. If desired, an additional extraction of thematerial may be carried out with a suitable solvent such as alcohol, inorder to improve the color or flavor of the final product.

The relative degree of removal of aqueous-alkaline soluble substancesfrom the starting soy meal may be readily ascertained from the dry basisprotein analysis of the extracted product separated from the extractionmedium following extraction. From a starting value of approximately 57.0percent (dry basis) protein in the final or end product, successivelymore thorough extraction or removal of aqueous-alkaline solublesubstances may be carried out on the starting material until anextracted product containing only -45 percent protein is obtained. Theapproximate relationship between solubles removal of aqueous-alkalinesoluble substances during the extraction step, percentage of residualprotein in the final product and yield is indicated in the followingtable:

From the above relationships, it is apparent that it is of economicadvantage to restrict solubles removal and thereby control yield at thehighest possible level consistent with product quality. On the otherhand, it has been found that the materials which contribute to adeleterious flavor are largely removed as aqueous-alkaline solublematerials in the extraction step and that the amount of proteinremaining in the extracted product makes it necessary to carefullycontrol the subsequent drying operation in order to preserve the desiredabsorptive properties in the final end products. In accordance with theinvention, it has been found that a minimum solubles removal of about 60percent, preferably about 65 percent or more, should be effected in theextraction step in order to produce an end product having improvedsorptive and emulsifying properties. In general, I prefer to effectsolubles removal of between about 60 to about 85 percent so that thefinal soy product of the invention has a protein content (dry basis) ofbetween about 20 to about 45 percent.

Following the extraction step and separation of the extract from theextracted product, as by mechanical pressing or other conventionalmeans, the extract may be discarded or, if desired, employed as thestarting material for preparing other soy products. In accordance withthe invention, the extracted product is then dried under mild orcontrolled drying conditions so as to avoid deleterious modification ofthe remaining protein and the cellular structure of the product. Bycarrying out drying of the extracted product under such controlledconditions, it has unexpectedly been found that a final soy productpossessing significantly improved sorption and emulsifying properties isobtained. While various modes of drying may be utilized, it has beenfound that in general the temperature of the extracted product shouldnot be permitted to exceed approximately 250 F. during the dryingoperation and should range between about F. and about 250 F. Preferably,the product temperature should range between about F. and 210 F. Optimumresults have been obtained, for example, by drying the extracted productin a tunnel dryer at a temperature of 180 F. for a period of about 90minutes or by spray drying at a temperature of about 180 F. for 510seconds. The higher the temperature employed within the above statedranges, the shorter the heating period or residence drying time of theextracted product required to effect the desired drying thereof.Conversely, the lower the temperature employed within the above statedranges, the longer the heated period of residence drying time of theextracted product required to effect the requisite degree of drying.Thus, the drying conditions, i.e. temperature and drying time, should beregulated and controlled as to achieve the necessary degree of dryingwhich preserves the improved sorptive properties of the soy materialwithout deleterious modification of the remaining protein of theextracted product and of the cellular structure of the product.

It is essential that scorching or glazing of the extracted product, suchas results from the higher temperatures employed by the prior art indrying, be avoided. Thus, the use of high temperature, long residencetime drying operations such as are carried out in rotary kiln equipmentknown to the trade result in the formation of a completelyunsatisfactory product. The combination of rolling action, protein filmforming and heat denaturization of the protein produce a casehardeneddried pellet that resists liquid penetration and therefore does notfulfill the objectives of the present invention. The preferred dyringmethods are those which expose the maximum surface area of the extractedproduct to drying air and thereby promote rapid moisture evaporationwith a minimum rise in the product temperature so as to avoiddegradation of the protein and the cellular structure. Satisfactoryproducts with improved sorptive and emulsifying properties have beenobtained, for example, by tunnel drying the extracted product at atemperature of approximately 180 F. for about 1 hour to 90 minutes andby flash or spray drying the extracted product under conditions suchthat a maximum product temperature of more than about 250 F. is notexceeded. It will be understood that other equivalent drying methods mayalso be utilized. It should be understood that the time of drying isinversely proportional to the drying temperature. At spray dryingconditions, the drying time will be between about 5 to 10 seconds; atlow vacuum or tunnel drying temperatures such as 140 F., the time may beas long as 3 hours or more. The drying time as a function of temperaturemay be expressed by the equation T k/t where T is temperature in degreesFahrenheit and t is time. The constant k will depend on the type ofdrying equipment used and the conditions of operation.

The sorptive and emulsifying properties of the soy products of theinvention may be further enhanced by forming the dried residue in suchmanner as to produce a product form which is highly receptive to liquidabsorption. This may be accomplished, for example, by forming theextracted product into granules before tunnel drying within the abovestated temperature range and then using the dried product in granularform or, if desired, mechanically reducing the desired product in sizeto the desired mesh. Also, for example, the extracted product may bespray dried directly to powder form. An illustrative product form andsize which has been found satisfactory is 50 mesh powder form, but itwill be understood that products having a size of, for example, 12-20mesh and powders having a size of 200-300 mesh are also useful. However,it will be further understood that other forms and sizes may be employeddepending upon the particular end use.

In particular, it has been found that the oil absorption properties ofthe final soy product are influenced to some extent by the final dryform of the product. This may be determined from the bulk density ormicroscopic examination of the final product. Thus, if the extractedproduct is subjected to wet abrasion conditions, such as being forcedthrough small nozzles in spray drying or being impringed on high speedrotary discs in a flash dryer, the material will exhibit a lower bulkdensity of about -22 lb./cu. ft. The material also exhibits someplasticity and appears to have a tendency to flow and fracture intolongitudinal pieces. Under dry abrasion conditions, on the other hand,the cellular matter of the material appears to form into relativelyregular fragments which pack more densely and therefore possess a higherbulk density on the order of about 22-45 lb./cu. ft. Thus, as shown inExample 5 hereinafter, a soy product of the invention produced in powderform by spray drying, exhibits superior oil absorption properties. Whilethe precise mechanism involved is not fully understood, I believe thatthe improved oil absorption results from maintenance of capillarywicking of the modified cellular structure of the soy product a producedby my process.

The products obtained through the practice of the invention arenon-hygroscopic and free-flowing and exhibit a bland to slight nutcereal flavor, odor and texture which is equal or superior to that ofpresently available soy products. While the products in the form offinely ground powders are readily dispersible in water, they are notsoluble. These products thus avoid many of the drawbacks of soy flour,for example, which possesses an undesirable stickiness or gumminess,texture effects and flavor. The modified cellular, spongelike characterof my novel soy product is evident under microscopic examination. Theimproved soy product produced by the process of the invention ischaracter'- ized by the following analysis:

Protein (dry basis) 20 45% by weight Moisture 6.0 10.0% by weight Ash3.5 4.5% by weight pH (water slurry) 7.0 8.5

Bulk density l0 24 lb./cu. ft. Extractables (percentage of productsolids removable by e further water leaching) 27.0 35.0%

The soy products of the invention possess a favorable amino acidbalance. A typical amino acid analysis for,

a soy product of the invention is as follows:

gm./.l00 gms. of Amino Acid gm./l00 gms. (100% protein Lysine 1.79 4.99Histidine 0.79 2.20 Arginine 1.84 5.13 Aspartic 3.63 10.13 Threonine1.48 4.13 Serine 1.65 4.60 Glutamic 4.86 13.56 Proline 1.45 4.05 Glycine1.45 4.05 Alanine 1.63 2.55 Valine 1.64 2.58 Methionine 0.48 1.34lsoleucine 1.47 4.10 Leucine 2.63 7.34 Tyrosine 1.16 3.24 Phenylalanine3.5 l 9.79 Cystine 0.39 1.09 Tryptophane 0.52 1.45

(Chemical) As stated, and as illustrated by the test results set forthhereinafter, the soy products of the invention display markedly enhancedand superior liquid sorption and emulsifying properties. Thus, myproducts are capable of abosrbing up to approximately 10 parts of waterto one part of product or up to 10-14 times its weight in water at roomtemperature, up to approximately 6 parts of oil to one part of productor up to 2.5-3 times its weight in oil at room temperature and largeamounts of other liquids such as up to approximately 6 parts ofisopropyl alcohol to one part of product. In contrast, the best soyproducts presently available absorb up to 7 parts of water to one partof product, up to 2 parts of oil to one part of product and up to 3parts of isopropyl alcohol to one part of product.

Because of its superior water and oil sorption properties, the soyproducts of the invention are useful in various applications, includingindustrial and edible products, which require thickening, emulsifying,dispersing, stabilizing, flocculating, fixing or holding of water and-/or oil and/or solvents of various types. Among the fields of usage formy novel soy products may be mentioned agricultural sprays, calkingcompounds, oil refining, soaps and industrial powders, foundry products,polishes and cleaning waxes, explosives, absorbent papers, mining, watertreatment, cosmetics, pharmaceuticals, and gravy-type pet foods. The soyproducts of the invention may also be used in various food products suchas cake mixes, package soup mixes, spreads, oilbase salad dressings,icings, candies, cereals and meat products. For example, it has beenfound that the soy products of the invention are particularly useful inreducing cooking shrinkage in meat products such as meat patties and thelike. In fact, the unexpected oil and water emulsifying properties ofthe invention provide greatly improved reduction in shrinkage losses inmeat products. The emulsifying properties of the product bind and holdboth fat and the aqueous juices found in themeat to retain them oncooking.

The following examples illustrate the invention:

EXAMPLE 1 Clean, dehulled, defatted soy flakes (100 parts) which hadbeen heat treated sufficiently for solvent removal, but not highlydenatured, were slurried with water (1,000 parts) to which had beenadded calcium hydroxide (2 parts). The resulting mixture was stirred for30 minutes at a temperature of F. and the extracted product was thenseparated from the extract by wet mechanical screening. The solidextracted product was again slurried with water l ,000 parts) at atemperature of 80 F. for minutes and expressed in mechanical dewateringmachinery to a semi-dry pulp.

The semi-dry pulp, representing approximately onethird of the originalflakes (dry weight basis) was formed into granules and dried in aconventional tunnel dryer at a temperature of 180 F. for a period of 90minutes. The analysis of the dried granules was as follows:

Protein (dry basis) 35.5% Moisture 7.0% Ash 4.0% pH (water slurry) 7.5

EXAMPLE 2 In order to compare the liquid absorption properties of theproduct of Example 1 with those of available soy products, samples of 3typical commercial soy products and the special soy product of Example1, all in'50- mesh powder form, were placed in beakers. Measured volumesof water, vegetable oil and isopropyl alcohol, respectively, at atemperature of 70 F. were added to a sample of each product and mixed inwith 2 minutes of hand stirring. The volume of each liquid absorbed(with no bleeding of free liquid from the paste formed) by each samplebefore the mixture became fluid enough to pour from the beaker wasrecorded as follows in terms of the volumes of liquid absorbed per 1part by weight of the soy products:

The following test was carried out to demonstrate that the superiorabsorption properties of the soy products produced by the process of theinvention may be utilized to combine two incompatible liquids such asoil and water into a homogeneous paste. The same pow dered soy productswere employed as in Example 2 and to a sample of each was added asufficient volume of vegetable oil at 70 F. was then added andhand-stirred until a non-pourable smooth paste was obtained with no freeliquid. The amounts of oil and water combined with each part by weightof each sample powder was recorded as follows:

Soy Product Volumes Absorbed 2 vol. oil with 4.5 vol. water -ContinuedVolumes Absorbed 1 2.5 vol. oil with 6.0 vol. water 4.5 vol. oil with7.0 vol. water Soy Product absorption type Soy product of Example IComparable results may be achieved in producing other homogeneouscombinations of incompatible liquids such as water and gasoline, oil andalcohol, etc.

EXAMPLE 4 The following test was carried out to demonstrate theimportance of effecting removal of more than 60 percent, preferably 65percent or more, of the aqueousalkaline soluble substances from thestarting material during the extraction step in order to produce a soyproduct having the desired properties.

One sample of clean, dehulled, defatted and desolventized soy flakes (1part) was slurried with water 10 parts) containing no alkaline materialfor a period of 5 minutes at a temperature of F. The resulting slurrywas separated in a cheesecloth bag and the extracted product was shapedinto granules by forcing through a screen having a 0.0964 inch mesh anddried in a tunnel dryer for 1 hour at a temperature of 180 F. Thegranules were then corn mill ground to pass mesh. The mild extractionconditions employed resulted in removal of 45 percent of the watersoluble substances, including carbohydrate and proteinaceous materials,from the starting material. The soy product produced by the aboveprocedure exhibited a bitter, beany flavor.

Following the procedure of Example 2, it was found that one part of thesoy product absorbed 5 volumes of water and 1.6 volumes of vegetableoil.

A separate sample of clean, dehulled, defatted and desolventized soyflakes (1 part) plus calcium hydrox ide (0.02 parts) was slurried withwater (10 parts) for a period of 20 minutes at a temperature of 70 F.The resulting slurry was separated in a cheesecloth bag, wash water wasadded to the extracted product in the bag and then the product wasre-squeezed dry. The extracted product was shaped into granules byforcing through a screen having a 0.0964 inch mesh and dried in a tunneldryer for one hour at a temperature of F. The granules were then cornmill ground to pass l00 mesh. The more thorough extraction conditionsemployed resulted in removal of 70 percent of the aqueous-alkalinesoluble substances, including carbohydrate and proteinaceous materials,from the starting material. The soy product produced by the aboveprocedure exhibited a bland flavor.

Following the procedure of Example 2, it was found that one part of thesoy product absorbed 9 volumes of water and 3.2 volumes of vegetableoil.

EXAMPLE 5 The extraction procedure of Example 1 was followed to producean extracted product in the form of a semidry pulp.

One sample of the wet extracted product was spray dried through anair/product nozzle with the spent air at a temperature of 225 F. Thetime of drying was about 5 seconds. The dried soy product was thenscreened to pass 200 mesh. Following the procedure of Example 2, it wasfound that one part of the resulting soy product absorbed 8 volumes ofwater and 6 volumes of vegetable oil. The soy product had a bulk densityof 12 lb./cu. ft. and, under microscopic examination, had the appearanceof large, long sections of cellular material.

A second sample of the wet extracted product was formed into in.granules and dried in a tunnel dryer for a period of 1 hour at atemperature of 180 F. The dried soy product was then hammer mill groundto pass 200 mesh. Following the procedure of Example 2, it was foundthat one part of the resulting soy product absorbed 7 volumes of waterand 3 volumes of vegetable oil. The soy product had a bulk density of 20lb./cu. ft. and, under microscopic examination, had the appearance ofroughly square, regular fragments of cellular material.

A third sample of the wet extracted product was dried in a rotary kilnat a temperature of 350 F. for a period of 1 hour. The dried soy productwas then hammer mill ground to pass 200 mesh. Following the procedure ofExample 2, it was found that one part of the resulting product absorbed3.5 volumes of water and 1.8 volumes of vegetable oil. The soy producthad a bulk density of approximately 2224 lb./cu. ft. The product wasdiscolored as compared with the products produced by spray drying andtunnel drying under the conditions described above.

EXAMPLE 6 Clean, dehulled, defatted and desolventized soy flakes parts)were slurried with water (100 parts) to which had been added sodiumhydroxide (0.2 parts) and sodium sulfite (0.1 part). The mixture wasstirred for 30 minutes at a temperature of 80 F. and then separated in aMercone C-400 centrifuge. The solids were collected and reslurried withwater (100 parts) at a temperature of 80 F. for minutes. The slurry wasthen separated in a Mercone C-400 centrifuge. The ex tracted product wasformed into granules by forcing through a screen having a 0.0964 inchmesh and tunnel or oven dried at a temperature of 200 F. for 1 hour.

The resulting soy product exhibited excellent water and oil absorptioncapacity.

EXAMPLE 7 Clean, dehulled, defatted and desolventized soy flakes (10parts) were slurried with water (100 parts) to which had been addedcalcium hydroxide (0.15 parts). The mixture was stirred for 20 minutesat a temperature of 90 F. The solids were separated from the extract andreslurried with water (100 parts) at a temperature of 90 F. for 20minutes. The extracted product was separated from the extract, formedinto granules and tunnel or oven dried at a temperature of 160 F. for 2/2 hours.

The resulting soy product exhibited excellent water and oil absorptionproperties. In particular, the resulting product produced food emulsionshaving greatly improved properties. I have found that the materialproduced by the process of the invention may be added to meat productsto produce an improved food product which does not exhibit the lossnormally present in preparation by cooking. In particular, a superiormeat patty can be produced using the resulting soy product. The pattyformed using the product has the great advantage of being less expensivein formulation than standard patties and also is superior in retaining agreater proportion of fat and aqueous juices and other standard pattymixes. The protein content of the patty is increased by the added soyproduct and flavor and texture are enhanced.

It is well known that there are considerable portions of our commercialtype of meats that result in waste, since they either contain anexcessive amount of fat or are too tough to make an attractive consumerproduct. As a result, such less desirable meats are sometimes discarded,put into animal foods, rendered into lard and fats or sold at very lowprices. Unfortunately, many of these meats are very flavorful andcontain nutritious amounts of protein, yet up to the present time, nowholly successful product or use has been discovered to make such meatsparticularly desirable for human consumption.

Many additive or extender type of materials have been added to presentlyacceptable lower priced meats to make them more flavorful, increase thebulk and reduce their cost. .For example, cereals, bread crumbs gluten,processed starch, vegetable gums, etc., have been added to meats such asground beef to achieve the above-described results. However, it iswidely recognized that meats of a high fat content or beingcharacteristically very tough are not always a saleable or profitableproduct which is ordinarily suited for human consumption. The additionof currently available additives or extenders to these types of meatsstill has not provided a wholly satisfactory product.

A well recognized disadvantage of meats having a relatively high fatcontent is the amount of shrinkage of such meats during ordinary cookingprocesses. The consumer must purchase an amount in excess of what wouldordinarily be required of less fatty-type meats to obtain a cooked meatproduct of suffcient size and weight.

It would, therefore, appear to be advantageous to provide a meat productwhich would utilize meats which are less desirable because of high fatcontent or characteristic toughness, and yet be flavorful, nutritiousand contain a relatively high percentage of protein or at least morethan is present in fat cuts of meat.

In accordance with the present invention, a new and improved foodproduct is provided in acomposition comprising (a) a meat portion, saidmeat portion normally containing at least about 5 percent by weight fatbased on the total weight of the meat portion, (b) a protein comprisingthe protein material previously described, and (0) water and optionalbinders, flavoring and food coloring. The protein material is normallypresent in the total composition in an amount from about 3 /2 to about10 percent by weight based on the total composition. Although the aboveis a preferred composition, it is to be understood that the compositionof the invention can also be obtained in a composition comprising theprotein material only and a meat portion.

The term meat as used herein is intended to include ordinary meats suchas beef, lamb, pork, fowl, fish and the like.

The method of mixing together the above materials is not critical;however, it is necessary that the product be mixed sufficientlythoroughly that the emulsifier is distributed uniformly enoughthroughout the mix to be able to bind the water and fat.

In addition to the meat and protein emulsifier material itself, themixture may contain optional binders, flavoring, coloring, etc. Suitablebinders that may be employed include egg albumen, isolated soy protein,

and the like. It has been found that from about to about 30 percent byweight of additional binder is satisfactory in the protein portion toprovide sufficient cohesiveness to the ultimate protein-meatcomposition, i.e. to improve the compositions resistance to crumbling orbreaking apart under normal handling conditions or during the cookingprocess. Although any of the above-mentioned binders may be employed inthe invention, it has been found that isolated soy protein isparticularly useful; however, it is not necessary to use any bindersunder most circumstances. Various commercially available meat flavorsmay be added to the protein portion to provide additional or differentflavors. Also, various spices and colors can be employed to providedesirable flavoring and appearance. If the protein emulsifier materialis added in a dry or powdered form, water will normally be added tohydrate the emulsifier material.

The protein emulsifier portion of the composition serves a veryimportant function. The protein emulsifier portion may be admixed with ameat composition containing a high percentage of fat, e.g. from about toabout 75 percent by weight fat. A resulting product can be obtainedwhich contains a higher percentage of protein than does the meat portionalone and a correspondingly lower amount of total fat. Therefore, theprotein mixture provides a means for economically upgrading low gradesof meat to provide a high protein meat product which is reasonablypriced to the consumer.

In addition, the protein emulsifier may be admixed with lean cuts ofmeat, e.g. meats containing below about 20 percent by weight fat, toprovide a means of extending or increasing the bulk of such meats andstill retain a desirable meaty texture. In each mixture, the proteinportion not only serves as an extender, but also tends to retain asubstantial amount of the aqueous natural juices within the meat mixturewhich otherwise would be lost during the cooking process.

The superior emulsifying and sorptive properties of the protein materialproduced by the invention, due to the modified cellular, sponge-likecharacter of the product, is able to sorb a greater proportion of theaqueous juices and fats released during the cooking step in preparingmeat-type products. The fats and aqueous juices are emulsified and heldin the modified cellular structure, e.g. formed from the particulate cellular material produced by alkaline extraction of soybean oil mealand/or flakes. Even prior to cooking, for example, after mixing of ameat product such as a meat patty, the modified cellular structure sorbsand emulsifies aqueous juices and fat to provide a stable meat product.

The meat portion employed in the composition of the invention can beselected from a variety of commercially available types of meat. Thepresent invention has its most practical application where the meatportion contains from about 20 to about 75 percent fat based on theweight of the meat portion alone. In order to provide meat productshaving a high protein content, yet being economical to produce, it iscurrently the practice to mix, for example, about one part of a high fatcontent meat with about 4 parts of a lean meat. Such a procedureutilizes high fat content meats, but because it requires the use of highpriced lean cuts of meat, the resulting mixture is still relativelyexpensive. It has now been discovered that, by the composition of thepresent invention, high fat content meats can be admixed with theprotein portion, as hereinbefore described, to obtain a resulting meatcomposition having a substantially higher percentage of protein thanthat 5 present in the meat alone. Such a meat composition eliminates thenecessity and cost of employing lean, expensive meats and yet provides aproduct which is flavorul and nutritious, has a desirable texture, andmore important, is economical to produce.

Another advantage of the meat compositions of the invention is theincreased speed at which a particular composition will cook as comparedwith the slower cooking speed of an all meat" portion of the meatemployed in the composition, said meat portion being of comparableweight and size and being cooked under the same conditions.

The following examples are illustrative of this facet of the invention,but are not intended to limit the scope thereof. In place of theparticular meat materials used in the examples, other meats may, ofcourse, be substituted to obtain meat compositions providingsubstantially the same result.

EXAMPLE 8 A patty mix costing approximately 40 cents per pound uncookedwas prepared by mixing:

nal weight.

EXAMPLE 9 A comparative patty formulation using a soy grits extendercoating costing 42 cents per pound uncooked was prepared by mixing:

5O 53 pounds lean boneless beef 40 pounds beef flank meat 21 poundswater 7 pounds soy grits The mix was prepared and cooked as described inExample 8. The average weight loss was 30.13 percent.

EXAMPLE 1O A comparative all meat patty formulation costing 55 cents perpound uncooked was prepared by mixing:

60 pounds lean boneless beef 40 pounds beef flank meat The mix wasprepared and cooked as described in Example 8. The average weight losswas 30.18 percent.

3 EXAMPLE 11 A second comparative patty formulation using a soy gritsextender and costing 45 cents per pound uncooked was prepared by mixing:

55 pounds lean boneless beef 40 pounds beef flank meat 5 pounds soygrits pounds water "It is apparent from the results shown by the aboveillustrative examples that the patty product produced using applicantsprocess possesses great advantage over products known in the art. Theproduct exhibits great advantages by enhancing moisture retention,taste, texture and cooking properties. Other advantages will be apparentto those skilled in the art.

" I claim:

1. A method of preparing an improved food product which exhibits ashortened time of preparation, increased retention of fat and aqueousjuices on cooking, and which does not crumble and lose shape on cooking,comprising mixing a meat portion containing fat and as an emulsifier adehulled, defatted, desolventized soy meal protein product containingless than about 40 percent of the aqueous-alkaline soluble substancesoriginally present in the soy meal and further containing be- TABLE IExample No. of Cost Per Weight Observation Samples Pound Un- Loss cooked8 2O 40 cents 22.37 substantially circular, (patty using finn, goodtaste and novel soy texture product) 9 42 cents 30.13 substantiallycircular, (patty using good texture, but soy soy grits) ofi" flavor 1020 55 cents 3018 irregular shape. sub- (all meat stantial shrinkage andpatty) curling, good taste and texture, not cooked as well as Example 8l l 20 45 cents 29.63 substantially circular. (patty usmg good texture.but soy soy grits) off flavor EXAMPLE 12 Parallel samples of meatpatties containing the spray dried product of Example 5, no emulsifierand soy grits were prepared from ground, deboned chicken containing68.4% water, 18.7% fat and 12.5% protein. The moist, ground chicken wasmixed with the dry, powdered emulsifier or soy grits to form ahomogeneous mix and formed into patties on a hand patty former. Thepatties were cooked as described in Example 8. The results of thecomparison are shown in Table II.

tween about 20 to percent by weight of protein on a dry basis which hasbeen dried at a temperature such that the temperature of the emulsifieris about l40F.-250F. for a period of approximately 180-60 minutes, themeat portion containing at least about 20% by weight fat based on theweight of the meat portion, binding the mixed portions together with5-30 percent by weight of the non-meat portion of the mixture with abinder selected from the group consisting of albumen and isolated soyprotein, and forming the mixed bound portions into a shape which doesnot TABLE II No. of Weight per Weight Emulsifier Rephcations Patty LossAfter Observations Cooking 0 5 46.6 grn. 40.4 very sticky, not machineworkable, shrivelled on cooking, did not retain shape high fry loss, badtaste and texture 7 soy grits 5 46.2 gm. 22.2 sticky, shrivelled oncooking and did not retain shape, better than l, probably not machineworkable, large fry loss, acceptable texture and taste 5 soy grits 546.3 gm. 30.6 same as 2, but greater fry loss 7 spray dried 5 46.4 gm.l0.4 machine workable, retained shape product of on cooking, uniform andlittle Example 5 shrinkage, not sticky, taste and texture veryacceptable crumble and break apart under normal handling andpreparation, cooking the formed mixture and retaining the fat andaqueous juices with the protein emulsifier in the mixture. I j

2. The method of claim 1 wherein the protein emulsifier is addedinproportions of between about 3 /2 and 10 percent. by weight of the mix.v

3. The method of claim 1 wherein the meat portion is selected from thegroup consisting of flank meat. and

navel meat. 7

4. The method of claim 1 wherein minor proportions of flavoring andcoloring are added to the meat and emulsifier mixture.

5. The process of preparing a substantially bland, free-flowing,non-hygroscopicsoy emulsifier product having improved liquid sorptionand emulsifying properties comprising the steps of treatingsubstantially de hulled, defatted and desolventized soy meal with anaqueous-alkaline material to solubilize and extract therefrom at leastapproximately 60 percent of the aqueous-alkaline soluble substances,separating the resulting extracted soy meal product from the extract anddrying the extracted soy meal product under controlled drying conditionsat a temperature such that the temperature of the extracted soy mealproduct is about F. 250F. for a period of approximately 180 60 minutesto substantially avoid appreciable denaturization of the remainingprotein in said extracted product and deleterious modification of thecellular structure of said extracted product.

6. The process of preparing a soy product as set forth in claim 5wherein between approximately 60 percent and approximately 85 percent ofthe aqueous-alkaline substances are extracted from said soy meal and theresulting soy product has a bulk density'of approximately 10-22 poundsper cubic foot.

7. The process of preparing a soy product as set forth in claim 5wherein said extracted soy meal product is formed into granules prior todrying thereof.

8. The method of claim 5 wherein the extracted soy meal product is driedin a thermal dryer at a temperature of appproximately 180 F. for aperiod of approximately 60-90 minutes.

9. The process of preparing a soy product as set forth in claim 5wherein the resulting soy product is mechanically reduced in sizefollowing drying thereof.

UNETED STATES PATENT ()FFNIE QERTH ECAE GE QQ PATENT NO. 1 35 885,052DATED I y 20, INVENTOMS) 7 Robert: P0 Starr It is certified that errorappears in the above-tdentitied patent and that said Letters Patent arehereby corrected as shown below:

Column 2, line 37, "desoluentized" should read -desolventized-=- Column4, line 22, heated" should read --heating-- a line 59 "50" should read-and-- Column l t, line 39, "130" should read --and-- igned and en'snineteenth 3) 9f August 1975 [SEAL] I Arrest:

O RUTH c. MASON c. MARSHALL DANN Arresting Officer (ummissimu'r uflau'msand Trademarks

1. A METHOD OF PREPARING AN IMPROVED FOOD PRODUCT WHICH EXHIBITS ASHORTENED TINME OF PREPARATION, INCREASED RETENTION OF FAT AND AQUEOUSJUICES ON COOKING,AND WHICH DOES NOT CRUMBLE AND LOSE SHAPE ON COOKING,COMPRISING MIXING A MEAT PORTION CONTAINING FAT AND AS AN EMULSIFIER ADEHYLLED, DEFATTED, DESOLVENTIZED SOY MEAL PROTEIN PRODUCT CONTAININGLESS THAN ABOUT 40 PERCENT OF THE AQUEOUS-ALKALIME SOLUBLE SUBSTANCESORIGINALLY PRESENT IN THE SOY MEAL AND FURTHER CONTAINING BETWEEN ABOUT20 TO 45 PERCENT BY WEIGHT OF PROTEIN ON A DRY BASIS WHICH HAS BEENDRIED AT A TEMPERATURE SUCH THAT THE TEMPERATURE OF THE EMULSIFIER ISABOUT 140*F.-250*F. FOR A PERIOD OF APPROXIMATELY 180-60 MINUTES, THEMEAT PORTION CONTAINING AT LEAST ABOUT 20% BY WEIGHT FAT BASED ON THEWEIGHT OF THE MEAT PORTION, BINDING THE MIXED PORTIONS TOGETHER WITH5-30 PERCENT BY WEIGHT OF THE NON-MEAT PORTON OF THE MIXTURE WITH ABINDER SLECTED FROM THE GROUP CONSISTING OF ALBUMEN AND ISOLATED SOYPROTEIN, AND FORMING THE MIXED BOUND PORTIONS INTO A SHAPE WHICH DOESNOT CRUMBLE AND BREAK APART UNDER NORMAL HANDLING AND PREPARATION,COOKING THE FORMED MIXTURE AND RETAINING THE FAT AND AQUEOUS JUICES WITHTHE PROTEIN EMULSIFIER IN THE MIXTURE.
 2. The method of claim 1 whereinthe protein emulsifier is added in proportions of between about 3 1/2and 10 percent by weight of the mix.
 3. The method of claim 1 whereinthe meat portion is selected from the group consisting of flank meat andnavel meat.
 4. The method of claim 1 wherein minor proportions offlavoring and coloring are added to the meat and emulsifier mixture. 5.The process of preparing a substantially bland, free-flowing,non-hygroscopic soy emulsifier product having improved liquid sorptionand emulsifying properties comprising the steps of treatingsubstantially dehulled, defatted and desolventized soy meal with anaqueous-alkaline material to solubilize and extract therefrom at leastapproximately 60 percent of the aqueous-alkaline soluble substances,separating the resulting extracted soy meal product from the extract anddrying the extracted soy meal product under controlled drying conditionsat a temperature such that the temperature of the extracted soy mealproduct is about 140*F. - 250*F. for a period of approximately 180 - 60minutes to substantially avoid appreciable denaturization of theremaining protein in said extracted product and deleterious modificationof the cellular structure of said extracted product.
 6. The process ofpreparing a soy product as set forth in claim 5 wherein betweenapproximately 60 percent and approximately 85 percent of theaqueous-alkaline substances are extracted from said soy meal and theresulting soy product has a bulk density of approximately 10-22 poundsper cubic foot.
 7. The process of preparing a soy product as set forthin claim 5 wherein said extracted soy meal product is formed intogranules prior to drying thereof.
 8. The method of claim 5 wherein theextracted soy meal product is Dried in a thermal dryer at a temperatureof appproximately 180* F. for a period of approximately 60-90 minutes.9. The process of preparing a soy product as set forth in claim 5wherein the resulting soy product is mechanically reduced in sizefollowing drying thereof.